Patent Literature 1 describes an electric vehicle charging system that heats a storage battery of an electric vehicle using heat transferred from a heat storage material included in the electric vehicle depending on the temperature of the storage battery when the storage battery is charged. With the system, the storage battery can be heated using the heat storage material included in the electric vehicle, and it is not necessary to secure electric power for heating by allocating a part of charging electric power during charging. In a case where the temperature of the storage battery is low, it is necessary that the storage battery is heated in order to prevent deterioration in the performance of the storage battery caused by charging. At this time, by supplying a heat source from the heat storage material included in the electric vehicle, electric power supplied from home can be efficiently used to charge the storage battery.